In a small rural library near my parents' summer cottage, I once found a little book about tabletop wargaming with miniatures. It wasn't a sociological study or anything, but simply a book about how to get started in the hobby. It talked about how to make terrain models, and measure ranges between units on a tabletop, and stuff like that. It also discussed basic rules, not in the sense of laying them down, but of discussing what things you should consider when inventing your own rules. All I really remember now was an example about how to distinguish the combat styles of Roman legions and barbarians, by treating Roman 6's as 5's and 1's as 2's. This would make the Romans steadier but give the barbarians more chance for a big hit.

A bit later I snagged a copy of Chainmail, which was technically one of the thin paperback supplement volumes to the original Dungeons and Dragons rules. It was rules for tabletop wargaming with miniatures in D&D fantasy worlds. Its main features were to let most miniature figures represent ten creatures, and assign them all exactly ten times the average hit points of the creatures involved.

If anyone is old enough to remember when D&D perversely quoted all distances in " (inches), but isn't old enough to know the answer, this is it: the ten-yards-to-one-inch scale (or ten feet indoors/underground) was the standard convention from tabletop wargaming in ancient or medieval settings.

I think I tried out a couple of Chainmail battles, but never really did any miniature wargaming. And I've seen, but never played, Warhammer, which is the same deal only still alive. I'm curious whether Warhammer includes any major departures from those old games, or whether it's really just the same.

I do know that D&D began as an adaptation of tabletop wargaming, based simply on letting the figures stand for individual people or creatures rather than groups. I think it was already a convention from the larger-scale games that units could improve with experience by acquiring some kind of veteran status. A guy named Dave Arneson added this element to an individual-scale game, and then a guy named Gary Gygax generalized the concept to infinite levels of experience, instead of just two. Suddenly an individual unit could have a long career of steady improvement, and thereby become a character rather than a unit.

I don't know much more than this about the birth of RPGs, though. I never owned the original D&D books, though I remember when they were for sale in a little boxed set. They were paperback, and crudely produced. The later appearance of the big hardcover books of Advanced Dungeons & Dragons, known now as the 'first edition', was a dramatic change for the whole hobby.